Each of the following options contains a set of four molecules. Identify the option(s) where all four molecules possess permanent dipole moment at room temperature.

Options

A. `BeCl_(2), CO_(2), BCl_(3), CHCl_(3)`
B. `NO_(2), NH_(3), POCl_(3), CH_(3)Cl`
C. `BF_(3), O_(3), SF_(6), XeF_(6)`
D. `SO_(2), C_(6)H_(5)Cl, H_(2)Se, BrF_(5)`

Answer

B, D

Explanation

`BeCl_2 and CO_2` have linear geometry where dipole moments cancel each other, so their dipole moment is zero. Also, `BF_3 and BCI_3`, molecules have symmetrical trigonal planar structure and `SF_6` has octahedral planar geometry with zero dipole moments.